Updated

Six British journalists are suing Scotland Yard over documents that show the police had them under surveillance for more than a decade.

Britain's National Union of Journalists says a public records request showed extensive surveillance of the six — who include three photographers, a video journalist, an investigative journalist and a reporter — by London's Metropolitan Police stretching back more than a decade.

The lawsuit adds to a drip-drip of public disclosures about British police secretly seizing journalists' telephone records in leak investigations. Several senior officers have recently acknowledged using anti-terrorism powers to uncover journalists' sources by combing through the records, drawing concern in Parliament and outrage from media groups.

British police declined to comment on the lawsuit announced Thursday.